Universal Avionics, a subsidiary of Elbit Systems (Chalet 198, Static A8), is nearing the final stages of developing a new type of flight management system (FMS), one that is embodied in software and can run inside a variety of hardware types.
The new FMS is called ClearVision Interactive or i-FMS, and although it is designed to work closely with other Universal Avionics products such as its InSight Integrated Flight Deck and SkyLens head-up display (HUD) and i-SVS (interactive synthetic vision system), the FMS will also be available to aircraft OEMs that want to design their own avionics interfaces for their aircraft. In the Universal Avionics version, this “software-based FMS,” under development for the past five years, will provide pilots a new and far simpler way to interface with FMSs, instead of having to look head-down and type on keypads and interpret arcane pages of information and symbols.
“This is a step in the roadmap to make avionics more simplified and semi-autonomous,” said Dror Yahav, CEO of Universal Avionics.
To understand what he means, it’s necessary to look back a few years. The concept of a software-based FMS isn’t suddenly new. After all, technically some avionics manufacturers completely bypassed the standalone FMS box and designed their own FMS software that lives inside their GPS navigators, for example, Garmin and Avidyne. A pilot flying with modern avionics by those manufacturers might not think they are using an FMS, but they are.
Years before Elbit bought Universal Avionics, which was a pioneer in the development of the FMS, “We wanted to buy a software-based FMS from our competitors,” said Yahav. But while there were plenty of avionics manufacturers building FMSs, none could figure out a way to cost-effectively separate the FMS box from the software that ran in it. Years of FMS development resulted in a product that, while sophisticated, was unalterably suitable only for a particular use.
Now as owner of Universal Avionics, Elbit’s and Universal’s avionics engineers and software developers are nearing the goal of delivering a software-based FMS. “Originally we were aiming to do another federated FMS box with a touchscreen,” he said. “But we decided to switch into a pure software open-architecture system.”
Of course, this meant completely rewriting the software the runs the FMS, as well as the human-machine interface (HMI). “We had legacy code back 20 to 30 years,” he said, “and additional stuff and components added. At [this] point, it’s hard for us to add new things. A lot of the system is relying on very old code and hardware. We said if we want to move to the future, we need to completely design from scratch. We have the know-how, the formulas, and the design capability, and [the new system won’t] carry all the burden of the legacy product.”
The result is a software-based FMS that can run on a variety of hardware systems, including commercial and military platforms, as well as on integrated modular avionics-type products (avionics that live on easily replaceable circuit boards) that most modern aircraft employ.
Just designing a new FMS, even software-based, wasn’t the only goal, however. “We realized that [aircraft] OEMs would like to distinguish their product and put their look and feel [in the flight deck],” he explained. The underlying FMS software, therefore, is a proprietary Universal Avionics design that isn’t accessible or changeable by the OEM. However, the HMI design is completely customizable by the OEM using application programming interfaces (APIs). “We’ll allow customers to design their own human-machine interface to give a particular look and feel associated with their product,” Yahav said. “We allow the customer to adapt the product to their flight decks and platforms.” This means not just picking the colors, he added, “but we allow them to design their own logic, like two clicks and a gesture. Or two fingers and one button, and new data information presentations. We open up the HMI and tell them, ‘Go do whatever you want.’”
On a deeper level, the FMS portion is separated into two functions, a core that does the computations and the HMI that can easily be changed. The core functions run on an Arinc 653 operating system that can be split into different applications running in separate partitions at varying design assurance levels (DAL). For example, one partition could run the primary flight display, a Level A DAL, while another runs a lower DAL maintenance function, and yet another a moving map.
“We separated the FMS and HMI, and allow the OEM to touch the HMI,” Yahav said. “The impact is not so high on the software because we don’t change the core software. We do not provide the source code from the core software. But the HMIs are APIs, and the HMI is flexible for the [OEM] to change.”
Over many years of FMS design, Universal Avionics has developed a large bank of interfaces with sensors and equipment in many aircraft types. “We collected interfaces and the software models to interact with those,” he explained. “This provides us the ability to adapt to different platforms, backward and forward."
Essentially, an OEM can still select which avionics hardware it prefers to install but then will also be able to play a much bigger role in designing the look and feel of the avionics. They won’t be hampered by restrictions imposed by the avionics manufacturer; currently, while there is some latitude in HMI design, a Garmin G3000 flight deck looks and feels pretty much the same in a Citation M2 or HondaJet. The same is true of a Collins Pro Line Fusion flight deck, where a Gulfstream G280 looks fairly similar to a Bombardier Global 6000, or a Honeywell Epic-based system in a Falcon shares many common features with the avionics in a Gulfstream.
The work that Universal Avionics is doing with its ClearVision i-FMS shows some of the unique opportunities that the system offers, and this is being demonstrated at the company’s Paris Air Show exhibit.
As Yahav explained, “We wanted to tackle the main challenge for FMS operation, the need to propose changes to the flight plan during a critical phase of flight: takeoff and landing.” Most pilots who fly in FMS-based flight decks have had to struggle with "hand-jamming” a new arrival and approach into the FMS during the busiest phase of flight while flying into a major metropolitan airport. The problem isn’t just that manipulating an FMS can be complicated, but that one of the pilots (or the lone pilot in a single-pilot jet) has to shift attention to the FMS exclusively, then seek verification of critical settings from the pilot flying, who is supposed to be concentrating on flying the airplane. Some might agree that more modern software-based systems like Garmin’s are simpler, but it still can be a lot of effort during a critical time.
Universal’s approach, thanks to the close relationship to parent Elbit, is to marry the Elbit-designed SkyLens wearable HUD with the new i-FMS, allowing pilots to manipulate the FMS by sight.
This is a revolutionary HMI, at least for aviation. The reason is that the i-FMS takes advantage of a key characteristic of the SkyLens HUD, which is that it effectively has an unlimited field of view (FOV). Traditional HUDs require the pilot’s head to be positioned precisely to look through the fixed-in-place combiner glass, and the FOV is typically 30 to 40 degrees, basically looking in front of the airplane through the windshield.
Because pilots wear the SkyLens HUD on their head, the FOV is wherever they happen to be looking: forward, up, down, to the side. The HUD imagery that the pilot can see will be wherever he or she is looking. That means looking in any direction while viewing ClearVision’s enhanced vision system (EVS), synthetic vision system (SVS), or combined vision system (CVS, a simultaneous overlay of EVS and SVS). In other words, the view of EVS or SVS imagery isn’t limited to just 40 degrees through the windshield, but rather is available in any direction.
The same holds true of flight and navigation symbology superimposed on the HUD imagery. If you want to view and manipulate a waypoint that is somewhere off your left shoulder, just look to the left, move a cursor over the waypoint by positioning your head to line the cursor up with the waypoint, then click a select button (it could be on the yoke or a hands-on-throttle in a military aircraft, but somewhere within convenient reach).
This is exactly the same as using a cursor-control device (CCD) to click on a waypoint on a moving map or even tapping the waypoint on a touchscreen except that you don’t have to look inside at a display. Your eyes are outside where they belong when flying an airplane.
That isn’t to say, however, that Universal Avionics designers think the only way to interact with avionics is via a wearable HUD. On the ground or in cruise flight, it makes perfect sense to use a CCD or touchscreen or even an old-fashioned FMS. But when things get busy, Yahav said, “we wanted all of it artificially augmented into the real environment.”
At the beginning, the i-FMS and SkyLens HUD combination will offer pilots a familiar transition into manipulating waypoints and making ordinary commands, bringing up menus, deciding where to go, selecting a new waypoint, etc. Further developments will see more integration between the pilot and the HMI and controlling functions by sight.
“We call if flight by sight,” he said. With the autopilot coupled to the i-FMS, “you can guide the airplane and fly without touching anything inside, by looking and clicking.”
At its Paris Air Show exhibit, Universal Avionics will demonstrate how the i-FMS software can run on different hardware and the interactivity of the HMI. Universal is also showing the software to aircraft manufacturers, “and the level of interest is very high,” Yahav said. “In business aviation, the [OEMs] would like to see more competition [in avionics]. This is a way to have more alternatives.” Another advantage of i-FMS is that an OEM will be able to speed up redesign of the HMI, instead of waiting for the avionics manufacturer to deliver software upgrades. Military customers are also interested, he said, because it will make it easier to design a hybrid commercial-military avionics system that integrates well with civil air traffic control environments. “It allows them to design their own HMI without the need to contract us,” he said. “And they can put in their own features and military look and feel, which is very important to them.”
Universal Avionics expects to certify the first version of i-FMS in about a year. “This is a step in the roadmap to make avionics more simplified and semi-autonomous,” said Yahav. “This is where the world is going.”